Chinese units?

[Hugmenot]

[snip] I think each game design depending on the size, takes me about 180-300 hours of work counting reading and studying.

Developing games takes us roughly 4 - 8 hours per scenario on average, including the time it takes to verify the OOB, prepare the document for final editing. game special rules, etc.
Games and supplements that require extensive special rules can require more time. For example, I spent over 120 hours on Land Cruisers and that does not include the time Matt spent developing scenarios.  I fear River Boats will take as much, if not more, development time.